Climbing Flat-bean vs Common Silver Hairgrass

Dalbergia obovata compared with Aira caryophyllea

Key Differences

• Climbing Flat-bean is Least Concern while Common Silver Hairgrass is Endangered.

Taxonomic Classification

Rank	Climbing Flat-bean	Common Silver Hairgrass
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class	Magnoliopsida (Dicots)	Liliopsida (Monocots)
Order	Fabales (Legumes & Allies)	Poales (Grasses)
Family	Fabaceae	Poaceae (Grass Family)
Genus	Dalbergia	Aira
Species	Dalbergia obovata	Aira caryophyllea

Evolutionary Relationship

Climbing Flat-bean and Common Silver Hairgrass share a common ancestor at the Phylum level: Magnoliophyta. (Flowering Plants)

Conservation Status

Climbing Flat-bean

LC — Least Concern

Common Silver Hairgrass

EN — Endangered

Physical Characteristics

Attribute	Climbing Flat-bean	Common Silver Hairgrass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Climbing Flat-bean

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Common Silver Hairgrass

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical grasslands and savannas, and flooded grasslands and savannas, among 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (Cameroon), Asia (Japan, South Korea), Europe (6 countries), North America (4 countries), Oceania and the Pacific (Australia), and South America (4 countries). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Climbing Flat-bean

Climbing Flat Bean, Vigna unguiculata subsp. sesquipedalis, commonly known as the Yard-long Bean or Asparagus Bean, is a vigorous climbing legume in the family Fabaceae widely cultivated across tropical and subtropical Asia for its extraordinarily long, edible pods. The pods, reaching up to 60–100 cm in length, are harvested when young and tender and are used extensively in Chinese, Southeast Asian, and South Asian cuisine. The species climbs trellises and poles using tendril-like, twining stems, producing purplish-white flowers that develop into the characteristic pendulous, slender bean pods. Like other Vigna species, it fixes atmospheric nitrogen through symbiotic bacteria in root nodules, improving soil fertility. Climbing Flat Bean is a warm-season crop requiring full sun, high temperatures, and adequate moisture, making it well suited to humid tropical and monsoon climates. It is an important food crop providing protein and vitamins for rural communities across Asia and is cultivated as a commercial vegetable in many tropical countries. The species is also grown in tropical America and Africa. Being a domesticated cultivar complex, its conservation status is not formally assessed in terms of wild populations, though the preservation of genetic diversity in cultivated landraces is an agricultural priority.

Common Silver Hairgrass

<em>Aira caryophyllea</em>, commonly known as Common Silver Hairgrass, is a slender annual grass belonging to the family Poaceae within the order Poales. This delicate grass is currently classified as Endangered on the IUCN Red List, reflecting significant conservation concern despite its historically broad distribution. It is typically found across a remarkable diversity of biome types, including tropical and subtropical moist broadleaf forests, grasslands, savannas, and flooded habitats, demonstrating notable ecological versatility. Its geographic range spans multiple continents, with documented populations in Africa (Cameroon), Asia (Japan, South Korea), Europe, North America, Australia, and South America. As an annual grass, it completes its life cycle within a single growing season, reproducing via wind-dispersed seeds. The inflorescence typically bears silvery, shimmering spikelets that give the species its common name. Biological traits such as average lifespan, body dimensions, and dietary specifics follow typical patterns for annual grasses — drawing nutrients from soil through root absorption rather than consuming other organisms. The endangered status suggests populations may be declining due to habitat loss, land-use change, or invasive species pressure across parts of its range.